A refractive index of the active layer is obtained by a photoluminescence inspection and an equivalent refractive index of the optical semiconductor element is computed. A refractive index of the optical waveguide layer is obtained by a photoluminescence inspection and an equivalent refractive index of the optical waveguide is computed. A film thickness of the refractive index adjustment layer is adjusted by etching the refractive index adjustment layer so that the equivalent refractive index of the optical semiconductor element and the equivalent refractive index of the optical waveguide are matched to each other. After adjusting the film thickness of the refractive index adjustment layer, a contact layer is formed on the second cladding layer and the refractive index adjustment layer. The optical waveguide is a passive waveguide to which no electrical field is applied and no current is injected.

A four-element light emitting diode with a transparent substrate, comprising a AlGaInP light emitting diode (LED) epitaxial wafer, and the surface of a GaP layer of the AlGaInP-LED epitaxial wafer is roughened into a bonding surface, a film is plated on the bonding surface and is bonded with a transparent substrate, and finally a GaAs substrate is removed. The transparent bonding disclosed herein can replace the GaAs substrate made of light absorption materials with the transparent substrate by substrate transfer technology, increasing the light emitting efficiency of the light emitting diode chip and avoiding extremely low external quantum efficiency caused due to the limitations of the material of conventional AlGaInP light emitting diode and the substrate; in addition, with the support of the cut path pre-etching technology, back melting or splashing during the epitaxial layer cutting process is avoided, light emitting efficiency is increased and electric leakage risk is eliminated.

Semiconductor LED layers are epitaxially gown on a patterned surface of a sapphire substrate (10). The patterned surface improves light extraction. The LED layers include a p-type layer and an n-type layer. The LED layers are etched to expose the n-type layer. One or more first metal layers are patterned to electrically contact the p-type layer and the n-type layer to form a p-metal contact (32) and an n-metal contact (33). A dielectric polymer stress-buffer layer (36) is spin-coated over the first metal layers to form a substantially planar surface over the first metal layers. The stress-buffer layer has openings exposing the p-metal contact and the n-metal contact. Metal solder pads (44, 45) are formed over the stress-buffer layer and electrically contact the p-metal contact and the n-metal contact through the openings in the stress-buffer layer. The stress-buffer layer acts as a buffer to accommodate differences in CTEs of the solder pads and underlying layers.

A composition and method for formation of ohmic contacts on a semiconductor structure are provided. The composition includes a TiAl.sub.xN.sub.y material at least partially contiguous with the semiconductor structure. The TiAl.sub.xN.sub.y material can be TiAl.sub.3. The composition can include an aluminum material, the aluminum material being contiguous to at least part of the TiAl.sub.xN.sub.y material, such that the TiAl.sub.xN.sub.y material is between the aluminum material and the semiconductor structure. The method includes annealing the composition to form an ohmic contact on the semiconductor structure.

A processing method for optical device wafers includes a shielded tunnel forming step and a dividing step. In the shielded tunnel forming step, a sapphire substrate is irradiated with a pulse laser beam having such a wavelength as to be transmitted through the sapphire substrate along regions corresponding to planned dividing lines. The light focus point of the beam is positioned inside the substrate from the back surface side of the substrate. Fine pores and amorphous regions that shield the fine pores form shielded tunnels along the planned dividing lines. In the dividing step, an external force is applied to the optical device wafer, and the optical device wafer is divided into individual optical device chips along the planned dividing lines. In the shielded tunnel forming step, a spherical aberration is generated by causing the laser beam to be incident on a condensing lens with a divergence angle.

A method of making an aluminum nitride (AlN) buffer layer over a silicon wafer for a light emitting diode (LED) includes preflowing a first amount of ammonia that is sufficient to deposit nitrogen atoms on the surface of a silicon wafer without forming SiNx, before flowing trimethylaluminum and then a subsequent amount of ammonia through the chamber.

According to one embodiment, a semiconductor light emitting device includes a light emitting chip and a fluorescent material layer. The light emitting chip includes a semiconductor layer, a first electrode, a second electrode, an insulating layer, a first interconnect layer, a second interconnect layer, a first metal pillar, a second metal pillar, and a resin layer. The semiconductor layer includes a light emitting layer, a first major surface, and a second major surface formed on a side opposite to the first major surface. The fluorescent material layer is provided on the first major surface and has a larger planer size than the light emitting chip.

LED devices having high-quality single crystal ZnO structures for spreading currents and extracting light out of the LEDs are disclosed. In one aspect, a LED device is provided to include a substrate; a first semiconductor layer exhibiting a first conductivity type and formed over the substrate; an active light-emitting structure formed over the first semiconductor layer, the active light-emitting structure operable to emit light under electrical excitation; a second semiconductor layer exhibiting a second conductivity type and formed over the active light-emitting structure; and a single crystal ZnO structure formed over the second semiconductor layer and including a bottom single crystal ZnO portion over the second semiconductor layer and a top single crystal ZnO portion extending from the bottom single crystal ZnO portion, wherein the bottom single crystal ZnO portion is a contiguous single crystal ZnO portion without having voids.

An optical device wafer processing method includes a shield tunnel forming step of applying a pulsed laser beam having a transmission wavelength to a sapphire substrate along an area corresponding to each division line from the back side of the sapphire substrate in the condition where the focal point of the pulsed laser beam is set inside the sapphire substrate, thereby forming a plurality of shield tunnels arranged along the area corresponding to each division line, each shield tunnel being composed of a fine hole and an amorphous region formed around the fine hole for shielding the fine hole. The optical device wafer processing method further includes a dividing step of applying an external force to the optical device wafer after performing a light emitting layer forming step, thereby dividing the optical device wafer along the division lines to obtain the individual optical device chips.

A substrate having an annealed AlN layer includes a substrate made of a material selected from among a group including sapphire, silicon carbide (SiC), and aluminum nitride (AlN), and an aluminum nitride (AlN) layer formed on the substrate and having a thickness of 100 nm or greater. The aluminum nitride layer is annealed at a prescribed annealing temperature and in a nitrogen/carbon monoxide (N.sub.2/CO) mixed gas atmosphere, and the nitrogen/carbon monoxide (N.sub.2/CO) mixed gas has a mixture ratio of N.sub.2 gas/CO gas in a range of 0.95/0.05 to 0.4/0.6.